This invention relates to a novel interlocked yarn and a method for making interlocked yarn. More specifically, it relates to an interlocked yarn including a plurality of continuous filaments having substantially no twist with the filament bundle having at least one of the filaments encircling the other filaments at spaced intervals along the length thereof to interlock the filaments together. The yarn is firmly held together by the interlock, thus eliminating the need for twisting or cohesive materials to hold the bundles together during processing or use.
It has long been recognized that the yarns must be twisted before fabrication into goods. The twist is necessary to contain loose ends and broken or wild filaments, to overcome filament flaring because of static electricity build-up during processing, and to minimize slub formation in the drop wires and heddles of the loom during weaving. However, twisting is expensive and time consuming and reduces the effective coverage of the yarn. It has been proposed to eliminate the need for twisting by interlacing the yarn, however, interlacing also has many disadvantages . Interlacing sometimes involves a separate operation from bulking and texturing and therefore increases costs of manufacture . Further, interlacing can usually be pulled out by high strain conditions used in fabrication. Consequently, interlaced yarn may also require some twisting for good processability. Additionally, the distance between entanglements in interlacing generally varies. Typically, interlacing is designed to come out during finishing or dyeing operations to improve coverage. However , sometimes the entanglement releases prematurely, which results in difficulty to further process the yarn. If the entanglement fails to release in processing, coverage in the fabric is impaired. An example of an interlaced or entangled yarn is shown in U.S. Pat. No. 3,846,968. An example of a yarn which has some twist in addition to an interlacing is shown in U.S. Pat. No. 3,911,655.